From ‘energy poverty’ towards sustainable tree-based bioenergy

When it comes to energy, countries—and in particular developing ones—could take a strong cue from Europe, where the use of bioenergy has been rising over the past two decades. Aware that the current reliance on fossil fuels is unsustainable from multiple perspectives, EU countries are increasing their use of renewable energy—including that stored in trees—for varied purposes, including electricity generation from biogas-fired power stations.

“All fossil energy sources have either reached or passed their peak production. Even with new discoveries of oil reserves in Africa, and technologies such as fracking for gas, we are running out of energy,” said Philip Dobie, Senior Fellow at ICRAF.

Dobie was speaking on 9 October at a seminar dealing with tree-based bioenergy, held at the twelfth meeting of the Conference of the Parties (COP 12) to the Convention on Biological Diversity (CBD) (CBD COP 12) in Pyeongchang, South Korea.

“A population of 9 or 10 billion by 2020 will be putting demands on energy of the sort you’ve never seen before,” he warned.

According to IEA and IPCC reports, only about 13% of the world’s energy supply was from renewable sources in 2007. Of this, 77% was bioenergy, most of it from woody biomass from trees and shrubs, pointing to the huge potential of trees as a source of sustainable energy.

Unlike temperate countries where the climates are cooler, developing countries in the tropics are able to produce biomass more readily. In sub-Saharan Africa, for instance, 80% of the energy comes from firewood and charcoal. “Charcoal is a potentially very damaging form of extracting energy from woodfuel, but it also has the potential to be an extremely valuable, and sustainable business,” said Dobie.

Dobie spoke of the bad rap woodfuel in developing countries often receives, because of health and deforestation concerns. In fact, the use of wood in developing countries is frequently considered “primitive,” he said. Yet developed nations are increasing their use of tree-derived energy, and even importing woody biomass for this purpose.

“In the energy policy plans of most developing countries, bioenergy does not feature at all. This means that in general, these policies are not sustainable. This is remarkable, considering that so many developing countries are sitting on so much energy in the form of trees. There is nothing more efficient than using the sun’s energy to provide us with something can be used as a source of biomass to generate different types of energy,” said Dobie.

Many trees contain not only woody biomass, but also products that can be converted into bioenergy to power machinery.A good example is Nypa fructans, a native south Asian palm that produces a sugary exudate that can be distilled into ethanol.

Dobie said many trees integrate well with food crops—they can be grown together—so farms produce food and fodder, and even gain from the better soil health trees bring, for higher food production.

He said, however, that researchers must provide answers to the pertinent questions needed to design optimal food-energy agroforestry systems. For instance:

Figuring out how much wood is needed and can be produced in particular localities,

Designing good models for short-rotation production of trees and shrubs, and use of tree biomass,

Innovating better cooking technologies,

Exoloring the potential of gasification of wood for power generation, and

Quantifying the effects of tree-based bioenergy on climate change.

In the same session, Mary Njenga, a post-doctoral fellow at the World Agroforestry Centre (ICRAF), spoke on some of the approaches that could make the use of charcoal more sustainable in sub-Saharan Africa, where the majority of charcoal producers use traditional low-efficiency kilns, with just around 10% of the biomass being converted to charcoal. A growing demand for firewood and charcoal spurred by population growth means that the rate of harvesting outstrips that of regeneration, she stated.

“Women are now cutting young trees for firewood,” said Njenga, causing real negative effects on wildlife and plant biodiversity due to loss of habitats. Njenga said African drylands—already vulnerable to degradation owing to their hot and dry climates— are the hardest hit by this phenomenon, as they are home to acacia trees, a favourite species for high-quality charcoal production.

“Besides biodivesity, the loss of trees in drylands goes hand in hand with the depletion of other values that trees bring, such as medicines, shade, and healthy soils.”

Making the woodfuel/charcoal industry sustainable could help solve the energy deficiency facing poor rural and urban households in the developing world. It would also lead to the restoration of drylands, she said. For this, actions to produce more wood and more efficiently convert and use it as energy are needed. These include:

Tree planting and farmer-managed natural regeneration of trees,

Efficient technologies for converting wood to charcoal (e.g. high-efficiency kilns and and gasifying stoves that produce both cooking gas and charcoal) and for using the fuel (e.g. improved cookstoves),

Fuel briquetting, which converts chardust and other biomass into usable fuel that is cheaper and less polluting than charcoal, and

Training and communication of best-practices throughout the entire value chain.

Njenga added that cross-sectoral woodfuel policies would start to bring transparency and efficiency into the largely unregulated, and corruption-ridden charcoal industry in Africa, worth an estimated 11 billion dollars annually.

Clearly, sustainable tree-based energy holds huge promise for Africa and the world. If this potential can be realised, people—including the poorest who are the worst-affected by energy poverty—as well as the environment, would be better off.

Daisy Ouya is a science writer and communications specialist with the World Agroforestry Centre (ICRAF). Over the past 15 years she has been packaging and disseminating scientific knowledge in the fields of entomology, agriculture, health, HIV/AIDS research, and marine science. Daisy is a Board-certified Editor in the Life Sciences (bels.org) and has a Masters’ degree in chemistry from the University of Connecticut, USA. Her BSc is from the University of Nairobi in her native Kenya. She has worked as a journal editor, science writer, publisher, and communications strategist with various organizations. She joined ICRAF in July 2012.
Twitter: @daisyouya